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T Ohashi

Publications and source records attributed to T Ohashi.

At least 361 records · Page 20Linked to original sources
PubMed1983

[R 1881 binding receptor and DHT concentrations in prostatic cytosol].

R 1881 binding receptor and DHT concentrations in human prostatic cytosol were assayed in surgically removed prostatic tissues of benign prostatic hyperplasia (BPH) and of the normal prostate. The normal prostates were obtained from totally cystectomized male patients with bladder cancer. Cytosols were incubated with 0.25--8.0 nM (6 points) of 3H-R 1881 in the presence or absence of excess radioinert R 1881 at 4 degrees C for 20 hours, thereafter treated with 0.5% dextran coated charcoal. Specific bindings were analysed in the form of scatchard plot analysis. Cytosol DHT levels were determined by radioimmunoassay reported previously. Steroid specificity studies revealed that R 1881 binding receptor was inhibited not only by androgens but also by progesterone, however, an addition of 1000 fold excess triamcinolone acetonide (TCA) reduced the inhibition by progesterone. As R 1881-receptor complex was eluted at the void volume of sephacryl S-200 chromatography, the receptor was considered to be 8-9S protein. Cytosol DHT levels were 35.5 +/- 13.6 pg/mg cytosol protein in BPH and 18.9 +/- 7.1 pg/mg protein in the normal prostates, showing a significantly higher value in the former (p less than 0.01). Kd and NBS of R 1881 receptor in BPH were 0.73 +/- 0.21 nM and 30.1 +/- 9.0 fmol/mg cytosol protein and those in normal prostate were 0.68 +/- 0.28 nM, 10.2 +/- 4.2 fmol/mg protein, respectively. NBS were also higher in BPH compared to the normal prostate (p less than 0.001). Moreover, DHT levels (y) and NBS (x) showed a significant correlation (y = 0.631 X + 15.764, r = 0.506).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1983

Pharmacological studies on supersensitization. X. Effect of tripelennamine, N,N-dimethyl-N',N'-dibenzylethylenediamine and N,N-dibenzyl-N',N'-dimethyl-1,2-propanediamine on the utilization of calcium in acetylcholine-induced contraction of isolated vas deferens of guinea pig.

Effects of tripelennamine, N,N-dimethyl-N',N'-dibenzylethylenediamine (DBED) and N,N-dibenzyl-N',N'-dimethyl-1,2-propanediamine (DBPD) on the isotonic contractions of isolated vas deferens of guinea pig were examined. Tripelennamine and DBED potentiated the contractile responses to acetylcholine and potassium chloride in Ca2+-free Tyrode solution. DBPD potentiated the contractile responses to lower concentrations of acetylcholine in Ca2+-free Tyrode solution, but did not affect contractions induced by potassium and higher concentrations of acetylcholine in Ca2+-free Tyrode solution. In depolarized vas deferens, tripelennamine and DBED augmented the maximum response to Ca2+, while DBPD did not affect the maximum response to Ca2+ and decrease the sensitivity to Ca2+. The contractile responses to acetylcholine in standard Tyrode solution were attenuated by lanthanum chloride and the residual contractions were not affected by tripelennamine, DBED and DBPD or decreased by DBPD. The contractile responses to potassium chloride were completely abolished by lanthanum chloride. The half-time of decrease in acetylcholine-contraction in Ca2+-free Tyrode solution was significantly different from that of potassium-contraction in Ca2+-free Tyrode solution. The contractile response of the glycerinated muscle piece of vas deferens to calcium chloride was potentiated by DBED, but was not affected by tripelennamine and DBPD. These results suggest that tripelennamine and DBED facilitate nonselectively the transmembrane influx of calcium from extracellular fluid and superficial calcium-binding sites. In addition, DBED increases the sensitivity of contractile element to cytoplasmic free calcium ion. DBPD potentiates the contractile response without affecting the transmembrane mobilization of Ca2+ induced by excitation of cell membrane.

Acetylcholine↗
PubMed1983

Pharmacological studies on supersensitization. XI. Inhibitory effect of dibenamine on tripelennamine-N,N-dimethyl-N',N'-dibenzylethylenediamine- and N,N-dibenzyl-N', N'-dimethyl-1, 2-propanediamine-induced supersensitivity of isolated vas deferens of guinea pig.

Effects of dibenamine on tripelennamine-, N,N-dimethyl-N',N'-dibenzylethylenediamine (DBED)- and N,N-dibenzyl-N',N'-dimethyl-1,2-propanediamine (DBPD)-induced supersensitivity of isolated vas deferens of guinea pig were examined. Dibenamine attenuated the degree of tripelennamine- and DBED-induced increase in sensitivity to acetylcholine and potassium in standard Tyrode solution, but did not affect the degree of DBPD-induced increase in sensitivity to acetylcholine. Dibenamine diminished the degree of tripelennamine-induced increase, but did not affect the degree of DBED-induced increase, in maximum response to Ca2+ of partially depolarized vas deferens. Dibenamine diminished the degree of tripelennamine- and DBED-induced augmentation of potassium-contraction in Ca2+-free Tyrode solution, but did not affect that of acetylcholine-contraction. These results suggest that dibenamine prevent tripelennamine- and DBED-induced increase in Ca2+-influx (including extracellular Ca2+-superficial Ca2+ exchange) induced by acetylcholine and potassium. It is also suggested that DBPD potentiates acetylcholine-contraction by dibenamine-insensitive mechanisms.

Acetylcholine↗
PubMed1983

Pharmacological studies on supersensitization. XII. Inhibitory effect of reserpine on tripelennamine-, N,N-dimethyl-N',N'-dibenzylethylenediamine- and N,N-dibenzyl-N',N'-dimethyl-1,2-propanediamine-induced supersensitivity of isolated vas deferens of guinea pig to acetylcholine.

Effects of tripelennamine, N,N-dimethyl-N',N'-dibenzylethylenediamine (DBED) and N,N-dibenzyl-N',N'-dimethyl-1,2-propanediamine (DBPD) on the isotonic contractions of isolated vas deferens of intact and reserpinized guinea pigs to acetylcholine were examined. Increase in sensitivity to acetylcholine induced by tripelennamine, DBED and DBPD was attenuated remarkably by reserpine. Tripelennamine- and DBED-induced increases in Ca2+-contractions were not affected by reserpine. Acetylcholine-contractions in Ca2+-free Tyrode solution were inhibited by reserpine, but K+-contractions in Ca2+-free Tyrode solution were not affected by reserpine. Tripelennamine- and DBED-induced increases in acetylcholine- and K+-contractions in Ca2+-free Tyrode solution were attenuated or abolished by reserpine. DBPD decreased cholinesterase activity of vas deferens of guinea pig, but DBED did not. These results suggest that, although the Ca2+-storage site utilized for acetylcholine-contraction is different from that for K+-contraction, tripelennamine- and DBED-induced increase in Ca2+-release from superficial Ca2+-binding sites induced by acetylcholine and K+ is inhibited by reserpine. It is also estimated that DBPD-induced supersensitivity to acetylcholine might be due to the inhibition of cholinesterase activity. However, the mechanism of inhibition of DBPD-induced supersensitivity by reserpine remained obscure.

Acetylcholine↗
PubMed1983

Immunocytochemical demonstration of the co-storage of noradrenaline with Met-enkephalin-Arg6-Phe7 and Met-enkephalin-Arg6-Gly7-Leu8 in the carotid body chief cells of the dog.

Cellular and ultrastructural localization of catecholamines in the dog carotid body was investigated by peroxidase-antiperoxidase method for light microscopy and by protein A-colloidal gold technique for electron microscopy, and compared with that of preproenkephalin A-related opioid peptides, i.e., Met-enkephalin-Arg6-Phe7 (Met-Enk-Arg-Phe) and Met-enkephalin-Arg6-Gly7-Leu8 (Met-Enk-Arg-Gly-Leu). Immunocytochemistry at the light microscopic level using consecutive semi-thin sections of Araldite-embedded tissue showed that some 30% of the chief cells contained immunoreactive noradrenaline together with Met-Enk-Arg-Phe and Met-Enk-Arg-Gly-Leu. A considerable number of chief cells exhibited immunoreactivities representing one or two of these three kinds of substances. A few chief cells showed none of the specific immunoreactivities. Immunoreactive adrenaline was not demonstrated in any cells of the dog carotid body. At the electron microscopic level, co-existence of noradrenaline with Met-Enk-Arg-Phe or Met-Enk-Arg-Gly-Leu in the same secretory granules was shown using the double labeling protein A-colloidal gold technique. Possible interactions of catecholamines and opioid peptides deserve consideration for the understanding of the chief cell's role in the carotid body chemoreceptor.

Adrenal Medulla↗
PubMed1983

[Assessment of urinary ferritin, CEA and beta 2-MG determinations in patients with urinary tract malignancies].

Ferritin, carcinoembryonic antigen (CEA) and beta 2-microglobulin (beta 2-MG) levels in urine from 45 patients with cancer (4 with renal adenocarcinoma, 7 with renal pelvic and ureteral cancer and 34 with bladder cancer) at various stages were clinically evaluated for their significance as parameter of urinary tract malignancies as compared to urinary fibrin/fibrinogen degradation products (FDP) and urine cytology. Ferritin levels for the poorly-differentiated and advanced stage groups were higher than those for the well-differentiated and early stage groups, and were especially high in 5 of the 7 patients with renal pelvic and ureteral cancer and all of the 7 patients with bladder cancer involving the upper urinary tract. These data suggest that determination of urinary ferritin is useful in the detection of urinary tract cancer involving the upper urinary tract. The upper limits of CEA levels were determined respectively according to white blood cell counts in urine. Although, CEA levels were elevated in the poorly-differentiated group and the advanced stage group compared to the well-differentiated and early stage groups, the values were positive in only 12 out of 52 cases (23.1%). These values seemed to be low compared to other reports. beta 2-MG levels increased significantly in the poorly-differentiated and advanced stage groups. However, most cases in the above groups were complicated with pyelonephritis or renal impairment. It is suggested that the urinary beta 2-MG secretion from cancer itself is not so significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoembryonic Antigen↗
PubMed1983

[Assessment of serum ferritin, CEA, beta 2-MG and PAP determinations in patients with urinary tract malignancies].

Ferritin, carcinoembryonic antigen (CEA), beta 2-microglobulin (beta 2-MG) and prostatic acid phosphatase (PAP) levels in serum from 77 patients with cancer (6 with renal adenocarcinoma, 9 with renal pelvic and ureteral cancer, 29 with bladder cancer and 33 with prostatic cancer) at various stages were clinically evaluated for their significance as a parameter of urinary tract malignancies. Although, ferritin, CEA and beta 2-MG levels in the poorly-differentiated and advanced stage groups of renal adenocarcinoma, renal pelvic and ureteral cancer, and bladder cancer were higher than those in the well-differentiated and early stage groups, those in most cases were within normal ranges. These proteins were not considered suitable for the screening test. Ferritin and beta 2-MG levels increased with advancement of the performance status (P.S.) proposed by Koyama and Saito; however, the latter was affected greatly by renal impairment. In prostatic cancer, PAP and ferritin levels were remarkably high in the poorly-differentiated group (PAP mean +/- S.E.: 57.6 +/- 22.5 ng/ml, ferritin 883 +/- 319 ng/ml) and the advanced stage group (27.2 +/- 10.5 ng/ml, 398 +/- 152 ng/ml) compared to the well-differentiated group (7.87 +/- 3.61 ng/ml, 88.5 +/- 25.8 ng/ml) and the early stage group (2.24 +/- 0.54 ng/ml, 186 +/- 91.7 ng/ml). PAP and ferritin levels of the untreated cases were positive in 10 out of 18 cases (55.6%) and 7 out of 18 cases (38.9%), respectively, and those of the relapsing cases were positive in 4 out of 7 cases (57.1%) and 6 out of 7 cases (85.7%), respectively. However, CEA and beta 2-MG levels were negative in most cases. Furthermore, increments of PAP and ferritin levels, especially that of the ferritin level, were significantly related to advancement of P.S., and high ferritin levels were obtained in all cases of P.S. 3 and 4. Therefore, determination of PAP and ferritin seems to be useful in monitoring prostatic cancer, and the latter to be useful in early detection of relapsing cases.

Acid Phosphatase↗
PubMed1983

External skeletal fixation using methylmethacrylate. Current technique, clinical results, and indications.

External skeletal fixation using self-curing acrylic resin was applied by inserting A-O cortical screws into the diaphyseal region and A-O cancellous screws into the epiphyseal and/or metaphyseal regions. The position of the screws was designed to secure three-dimensional fixation. Points of insertion are selected that avoid infected bone, open wounds, thick muscles, and skin that is relatively mobile during joint motion. After reduction the acrylic resin rather than conventional metal linking devices is used for fixation of the screws. Once the fixation is completed, it is adjustable and so rigid that exercises for joint function are possible. The apparatus is light in weight and sufficiently compact to fit under clothing. In the 204 patients treated by this method, open tibial fractures occurred in 123; nonunion or delayed union in 28; metaphyseal and epiphyseal fractures in 30; femoral fractures in ten children; and miscellaneous fractures and other conditions in 13. Nearly all of the operations were successful. Three patients had refractures after removal of the fixation device.

Adult↗
PubMed1982

[Endogenous androgen levels of human prostatic tissues].

Endogenous androgen levels of prostatic tissues in patients with benign prostatic hypertrophy (BPH) and untreated prostatic cancer (PC) were determined by radioimmunoassay using sephadex LH-20 column chromatography. By this assay procedure, it was possible to measure tissue androgen levels with only 30 approximately 40 mg weight of tissues. In BPH (n=20) the concentrations of steroids (mean +/- standard deviation, ng/g. tissue weight) were 5 alpha-androstane 3 alpha, 17 beta diol (A-diol), 2.31 +/- 1.29; dihydrotestosterone (DHT), 4.97 +/- 2.17; testosterone (T), 0.62 +/- 0.33. In PC (n=17) the concentrations were 5.51 +/- 3.23; 3.94 +/- 3.16; and 0.93 +/- 0.38; respectively. The concentrations of DHT were raised and the levels of A-diol were reduced significantly (P less than 0.01) in BPH compared with PC. Tissue DHT levels of PC were variable, but they could be classified in to two groups. One was below 2 ng levels (n=8) similar to those of non-androgen target tissues and the other was over 2 ng (n=19). The relationships between histological differentiation and tissue DHT levels in prostatic cancer were examined. In poorly differentiated cancer (n=4), DHT levels were low in all cases, furthermore even in well differentiated ones there were 4 cases with levels below 2 ng. Thus, the measurement of endogenous DHT levels of prostatic tissues was considered to be valuable for the judgment of androgen dependency in prostatic cancer.

Aged↗